Lee, YoonjinDominy, John E.Choi, Yoon JongJurczak, MichaelTolliday, NicolaCamporez, Joao PauloChim, HelenLim, Ji-HongRuan, Hai-BinYang, XiaoyongVazquez, FranciscaSicinski, PiotrShulman, Gerald I.Puigserver, Pere2015-01-052014Lee, Y., J. E. Dominy, Y. J. Choi, M. Jurczak, N. Tolliday, J. P. Camporez, H. Chim, et al. 2014. “Cyclin D1-CDK4 Controls Glucose Metabolism Independently of Cell Cycle Progression.” Nature 510 (7506): 547-551. doi:10.1038/nature13267. http://dx.doi.org/10.1038/nature13267.0028-0836http://nrs.harvard.edu/urn-3:HUL.InstRepos:13581218Insulin constitutes a major evolutionarily conserved hormonal axis for maintaining glucose homeostasis1-3; dysregulation of this axis causes diabetes2,4. PGC-1α links insulin signaling to the expression of glucose and lipid metabolic genes5-7. GCN5 acetylates PGC-1α and suppresses its transcriptional activity, whereas SIRT1 deacetylates and activates PGC-1α8,9. Although insulin is a mitogenic signal in proliferative cells10,11, whether components of the cell cycle machinery contribute to insulin’s metabolic action is poorly understood. Herein, we report that insulin activates cyclin D1-CDK4, which, in turn, increases GCN5 acetyltransferase activity and suppresses hepatic glucose production independently of cell cycle progression. Through a cell-based high throughput chemical screen, we identified a CDK4 inhibitor that potently decreases PGC-1α acetylation. Insulin/GSK3β signaling induces cyclin D1 protein stability via sequestering cyclin D1 in the nucleus. In parallel, dietary amino acids increase hepatic cyclin D1 mRNA transcripts. Activated cyclin D1-CDK4 kinase phosphorylates and activates GCN5, which then acetylates and inhibits PGC-1α activity on gluconeogenic genes. Loss of hepatic cyclin D1 results in increased gluconeogenesis and hyperglycemia. In diabetic models, cyclin D1-CDK4 is chronically elevated and refractory to fasting/feeding transitions; nevertheless further activation of this kinase normalizes glycemia. Our findings show that insulin uses components of the cell cycle machinery in post-mitotic cells to control glucose homeostasis independently of cell division.en-USJournal Article2015-01-0510.1038/nature13267